Invisible toxic chemicals similar to those contaminating groundwater south of Colorado Springs also are showing up in fast-food wrappers, according to a scientific study done with help from the Environmental Protection Agency.

The Environmental Working Group study, peer-reviewed and published Wednesday in the journal Environmental Science and Technology Letters, found the perfluorinated chemicals (PFCs) in grease-resistant wrappers -– including pizza box liners, sandwich and pastry packaging — from chains including Starbucks, Jimmy Johns, Taco Time, Chipotle and Quiznos. The chemicals can leach into food, potentially reaching consumers, the study authors said, urging companies to find safe alternative packaging.

Scientists from California and the Environmental Protection Agency collaborated in the research with final testing done at an EPA lab.

“We don’t have definitive answers for how much harm these chemicals are causing, but there are many reasons to be concerned,” EWG chemist Dave Andrews said.

“These fast food companies need to look at their supply chains. They need to evaluate alternatives and move away from this concerning class of chemicals because of the potential for human health impact and the fact that the chemicals do not break down in the environment,” Andrews said.

PFCs are chemical compounds used to make products resistant to stains, water, or heat. The same properties that make PFCs useful from cookware to dousing fuel fires on runways also prevent them from breaking down in the environment. EPA scientists have found PFCs contaminating water nationwide, including sites near military bases such as Peterson Air Force Base east of Colorado Springs, and have determined that PFCs now are widely dispersed in humans and wildlife. U.S. Air Force officials in November said the Department of Defense will spend more than $2 billion on studies and cleanup nationwide.

PFCs have been linked by scientists to low birth weights, cancers of the kidneys and testicles, and other problems. The effects are not well established. PFCs aren’t illegal, ranking among the most problematic of a growing number of unregulated contaminants that federal scientists are finding in water. The EPA in May issued a health advisory limit for PFCs in drinking water – 70 parts per trillion, tightened from a previous limit of 400 ppt.

Federal authorities have not followed up with legally-enforceable regulations or an advisory limit for PFCs in food packaging. However, the Food and Drug Administration last year banned three grease-resistant PFCs, including one, PFOA, that the EWG team found in fast food packaging.

Researchers say they collected 327 samples of sandwich and pastry wrappers, french fry bags, pizza boxes and other packaging from 27 restaurants in five states during 2014 and 2105. The researchers used a device that measures fluorine, a chemical indicator that PFCs may be present. About 40 percent of the food packaging samples tested positive for fluorine, and 20 of those samples were sent to an EPA lab for detailed analysis, EPA scientist Mark Strynar said. High resolution mass spectrometry was used and chemicals detected included PFCs, Strynar said.

The EPA lab tests found 70 percent, or 14 of the 20 wrappers, contained PFCs including the banned PFOA.

The study focused on newer types of PFCs with shorter carbon chains that manufacturers claim are less hazardous that older PFCs. EWG advocates contend there’s insufficient evidence those short-chain PFCs are safer.

PFCs have been used since the 1950s to make carpets, clothing, fabrics for furniture, paper packaging for food and cookware resistant to water, grease or stains. The chemicals also are used for firefighting at airfields. Over time, PFCs have spread widely in the environment, accumulating in human blood, wildlife and fish. EPA officials began investigating and in 2002 released an initial finding that PFOA might pose health risks. Manufacturers including 3M Corp. in 2002 voluntarily stopped producing PFOA.

Yet PFCs are being found at levels exceeding the health guidelines in groundwater and public drinking water supplies, such as those serving residents of Fountain, Security and Widefield south of Colorado Springs.

People are most likely exposed to PFCs by ingesting PFC-contaminated water or food and by using products that contain PFCs, according to the U.S. Centers for Disease Control. The extent of leaching from food packaging to food has not been established. CDC scientists who measured four PFCs in blood have found wide exposure in the U.S. population, but those PFCs may not cause health harm.

A global industry group representing makers of fluorinated chemicals on Wednesday said that many companies in the United States, Europe and Japan have stopped producing some types of PFCs. “There are now specific, modern, short-chain PFAS chemicals that have been carefully reviewed and approved for use in coating food-contact papers to keep grease, oil and moisture from seeping through the packaging,” American Chemistry Council spokesman Bryan Goodman said.

“So to find these chemistries in these products is neither surprising nor alarming, as long as they are approved for use by the U.S. Food and Drug Administration,” Goodman said. “Because use of short-chain PFASs in food packaging is highly and rigorously regulated, any further regulation of modern-day short-chain food packaging materials is unnecessary and would provide no further benefits to human health or the environment.”

Note: Story updated at 3 p.m. Feb. 1 with comment from American Chemistry Council.

Bruce Finley covers environment issues, the land air and water struggles shaping Colorado and the West. Finley grew up in Colorado, graduated from Stanford, then earned masters degrees in international relations as a Fulbright scholar in Britain and in journalism at Northwestern. He is also a lawyer and previously handled international news with on-site reporting in 40 countries.

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